On the use of 4:2 compressors for partial product reduction

The 4:2 compressor has transformed the standard frame of mind for counter based partial product reduction schemes by introducing the notion of horizontal data paths within stages of reduction. Since its inception by Weinberger in 1981, this concept has soared in popularity in many digital multiplication and multi-operand addition schemes. The application of 4:2 compressors has also been the focus of several studies promoting its use over booth receding schemes. This paper provides an in depth looks at the 4:2 compressor, and a novel layout scheme for optimal placement will be presented.